1. Technical Field
This invention relates to the field of air curtains used to create an airflow defined barrier in openings in buildings between interior and exterior or different conditioned spaces within the building for reduced energy use by environmental retention therebetween.
2. Description of Prior Art
Prior art devices of this type have been directed towards air curtains and associated air blower assemblies that include airstream conditioning such as heating. Typically, air curtains are limited to ambient air recirculation with the inclusion of heaters to condition the airflow as it leaves the blower through a directional outlet nozzle to form a laminar airflow barrier between openings. All known air curtain configurations condition the airflow pre or post blower, see for example U.S. Pat. No. 5,984,649.
Other heated air blower units have been developed for a variety of air heating applications with associated electric resistant coils, see for example U.S. Pat. No. 4,988,847 for defogging a bathroom mirror and well known portable electric heaters used for auxiliary point of use heating too numerous to list.